دانلود رایگان ترجمه مقاله مقرون به صرفه بودن نگه داری و نوسازی زیرساخت راه آهن (نشریه ASCE 2004)

مقرون به صرفه بودن نگه داری و نوسازی زیرساخت راه آهن

Cost-Effectiveness of Railway Infrastructure Renewal Maintenance

Abstract

U.S. Class I railways maintain their infrastructure through a mix of ordinary maintenance and periodic renewal of infrastructure components. Different railways use different proportions of ordinary maintenance and periodic renewal with little consensus as to the best combination. Furthermore, the cost-effectiveness of emphasizing one method over the other has not been analyzed using empirical data. The objective of this research is to investigate the cost-effectiveness of renewal-based maintenance strategies using high-level financial data from industry sources. The results indicate that maintenance strategies that place more weight on renewal result in lower unit maintenance costs, at least within a specified observable range. The results imply that if railroads constrain renewal maintenance to reduce overall capital expenditures, increasing maintenance expenses will more than offset temporary reductions in capital spending.

۱ Introduction

Since the railway infrastructure investment boom of the mid1980s, all Class I railroads have made significant efficiency gains in infrastructure maintenance that are the result of improvements in a number of areas. Technological advancements in infrastructure components such as cleaner and harder steel have reduced asset life-cycle costs. Improved component management has also reduced costs, for example, new developments in rail grinding and lubrication
IHHA 2001. Infrastructure maintenance delivery systems and maintenance equipment technology have changed considerably. Better measurement tools and cross-functional teamwork has transformed traditional engineering practices.

Railroads maintain their infrastructure using a combination of ordinary and renewal maintenance techniques. Ordinary maintenance generally includes the replacement of small quantities of infrastructure components using relatively small track gangs and small equipment, whereas renewal maintenance techniques involve the replacement of larger quantities of components with larger gangs and bigger, more sophisticated, and more expensive equipment. Ordinary maintenance activities are normally charged to operating expense and renewal maintenance programs to capital expenditures according to Surface Transportation Board
STB accounting requirements
U.S. Senate 1995.

Over the past 20 years, all Class I railroads have increased their use of renewal-based compared to ordinary maintenance, but the degree to which they do so varies substantially
Fig. 1. A Class I railroad is one that met a revenue threshold of $277.7 million in 2004 in the United States
AAR 2005. For the purposes of this analysis we calculated renewal-based maintenance cost using a procedure
described in the section on methodology that separates railroad capital expenditures into capacity- and maintenance-related components.